Pulmonary Embolism Diagnostic Devices and Associated Methods and Systems

ABSTRACT

Methods and devices are disclosed that, in various embodiments and permutations and combinations of inventions, diagnose and treat Pulmonary Embolism or associated symptoms. In one series of embodiments, the invention consists of methods and devices for identifying patients whose Pulmonary Embolism or associated symptoms are caused or exacerbated, at least in part, by blockages of one or more of the patient&#39;s internal pulmonary veins. In some instances, stenoses or other flow limiting structures or lesions in the patient&#39;s affected veins are identified. Further, in some instances the nature of such lesions and whether there is a significant disruption of blood pressure, or both, is ascertained. In some embodiments, methods and devices for applying one or more therapies to the blockages in the patient&#39;s pulmonary veins are provided.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to and the benefit of U.S. ProvisionalPatent Application No. 61/429,058, filed on Dec. 31, 2010, which ishereby incorporated by reference in its entirety.

FIELD OF INVENTION

The present disclosure relates to improved methods and devices fordiagnosing and treating CCSVI (chronic cerebrospinal venousinsufficiency) in patients with multiple sclerosis or other diseasesthat are due to or exacerbated by obstructions to blood flow and, moreparticularly, to methods and devices for identifying patientsparticularly likely to benefit from the delivery of one or moretherapies to treat such patients and methods and devices for deliveringsuch therapies.

BACKGROUND

Multiple sclerosis (MS) is an inflammatory disease of the nervous systemwhere the fatty myelin sheaths around the axons of the brain and spinalcolumn are damaged. As a result of this damage, the ability of nervecells in the brain and spinal cord to communicate with each other iscompromised. Almost any neurological symptom, including physical andcognitive disability, can appear with the disease. MS affects more than350,000 people in the United States and 2.5 million worldwide. In theUnited States, prevalence estimates are approximately 90 per 100,000people.

Beginning with the first description of the anatomy associated with MSby Jean-Martin Charcot in 1868, MS plaques associated with MS have beenknown to be centered or located around veins. Further, it has beenrecently shown that MS is significantly correlated with a conditioncalled chronic cerebrospinal venous insufficiency (CCSVI). CCSVI is acondition where people have obstructed blood flow in the veins thatdrain the central nervous system (the brain and spinal cord) and ischaracterized by multiple stenoses of the principal pathways ofextracranial venous drainage, the internal jugular veins (IJV) and theazygous veins (AZV), with opening of collaterals, clearly demonstratedby means of selective venography and magnetic resonance venography(MRV).

Stenosis literally means a “narrowing.” Here “stenosis” or its plural“stenoses” is an abnormal narrowing of the vein that restricts bloodflow. This abnormal narrowing may be the result of many things. Forexample, the abnormal narrowing maybe the result of a collapse of thevein, twisting of the vein, ring-like narrowings in the vein and othersimilar obstructions. Further, the abnormal narrowing may be the resultof severe venous problems including veins that are partially closed,underdeveloped, minimally formed or almost entirely missing. Inaddition, an abnormal or defective valve, septum, flap or membrane maynarrow, blocks or inhibit blood flow through the veins. Finally, thebuild up of plaque, fibrin or thrombus may cause an abnormal narrowingof the vein. With respect to MS, a consequence of a stenosis in a veinleads to problems with normal or efficient blood drainage from the brainand spine back to the heart.

Intravascular ultrasound (“IVUS”) combined with a technique calledvirtual histology (“VH”) has been particularly successful in recognizingthe morphology of atherosclerotic plaque in vivo (i.e., the location andcomposition of plaque in the patient's body). Current developments areunderway to also be able to recognize thrombus in vivo. FIG. 1illustrates a typical intravascular imaging system 2 that usesintravascular ultrasound (IVUS). FIG. 2 illustrates a typicalintravascular imaging system 2 that uses optical coherence imaging(OCT).

An example of an IVUS system is the s5i™ Imaging System sold by VolcanoCorporation of San Diego, Calif. Examples of OCT imaging systemsinclude, but are not limited to, those disclosed in U.S. Pat. No.5,724,978 issued Mar. 10, 1998 entitled “Enhanced accuracy ofthree-dimensional intraluminal ultrasound (ILUS) image reconstruction”with Harm Tenhoff as inventor, US Published Patent Application Nos.20070106155 entitled “System and method for reducing angular geometricdistortion in an imaging device” with John W. Goodnow and Paul Magnin asinventors and published on May 10, 2007, 20080287801 entitled “IMAGINGDEVICE IMAGING SYSTEM AND METHODS OF IMAGING” with Russell W Bowden, TseChen Fong, John W. Goodnow, Paul Magnin and David G. Miller andpublished on Nov. 20, 2008, 2004693980 entitled “REAL TIME SD-OCT WITHDISTRIBUTED ACQUISITION AND PROCESSING” with Nathanial J. Kemp, AustinBroderick McElroy and Joseph P. Piercy as inventors and published onApr. 9, 2009, 20080119701 entitled “ANALYTE SENSOR METHOD AND APPARATUS”with Paul Castella, Nathaniel J. Kemp and Thomas E. Milner as inventorsand published on May 22, 2008, 2004618393 entitled “CATHETER FOR IN VIVOIMAGING” with Larry Dick, Thomas E. Milner and Daniel D. Sims asinventors and published on Jan. 15, 2009, 2004646295 entitled “APPARATUSAND METHODS FOR UNIFORM SAMPLE CLOCKING” issued to Nathaniel J. Kemp,Roman Kuranov, Austin Broderick McElroy and Thomas E. Milner asinventors and published on Feb. 19, 2009, 2004884749 entitled “OCTCombining Probes and Integrated Systems” with Dale C. Flanders andBartley C. Johnson as inventors and published on Nov. 19, 2009 and WIPOPublished Patent Application No. WO200483635 entitled “FORWARD-IMAGINGOPTICAL COHERENCE TOMOGRAPHY (OCT) SYSTEMS AND PROBE” with Jonathan C.Condit, Kuman Karthik, Nathaniel J. Kemp, Thomas E. Milner and XiaojingZhang as inventors and published on Feb. 19, 2009, the collectiveteachings of which, in their entirety, are incorporated herein byreference.

Such imaging systems 2 may also include systems capable of identifyingthe makeup of the tissue and material of a patient's vasculatureincluding so called virtual histology (VH) systems. An example of a VHsystem is the s5i™ Imaging System with VH capability sold by VolcanoCorporation of San Diego, Calif. The imaging systems 2 may also includesystems for measuring the flow of blood in a patient's vasculature. Anexample of such a blood flow measurement system is a color-Dopplerultrasound imaging system sold under the brand name of Chromaflow® byVolcano Corporation of San Diego Calif.

In an exemplary imaging system 2, an intra-vascular ultrasound (IVUS)console 4 is electrically connected to an IVUS catheter 6 and used toacquire RF backscattered data (i.e., IVUS data) from a blood vessel. TheIVUS console 4 typically includes a computing device 8 comprising adatabase 10 and a characterization application 12 electrically connectedto the database 10 and adapted to receive IVUS data from the IVUSconsole 4 or directly from a transducer 14. Specifically, a transducer14 is attached to the end of the catheter 6 and is carefully maneuveredthrough a patient's arteries to a point of interest along the artery.The transducer is then pulsed to acquire high-frequency sonic echoes orbackscattered signals reflected from the tissue of the vascular object.Because different types and densities of tissue absorb and reflect theultrasound pulse differently, the reflected data (i.e., IVUS data) isused to image the vascular object. In other words, the IVUS data can beused (e.g., by the IVUS console 4 or a separate computing device 8) tocreate an IVUS image.

An exemplary IVUS image 16 is shown in FIG. 2, where the light and darkregions indicate different tissue types and/or densities. It should beappreciated that the IVUS console 4 depicted herein is not limited toany particular type of IVUS console, and includes all ultrasonic devicesknown to those skilled in the art (e.g., a Revolution® or EagleEye® IVUScatheter used in conjunction with an s5™ IVUS imaging system, all ofwhich are sold by Volcano Corporation of San Diego, Calif.). It shouldfurther be appreciated that the IVUS catheter 6 depicted herein is notlimited to any particular type of catheter, and includes all ultrasoniccatheters known to those skilled in the art. Thus, for example, acatheter having a single transducer (e.g., adapted for rotation) or anarray of transducers (e.g., circumferentially positioned around thecatheter or longitudinally along the catheter 6) can be used with thetypical imaging system 2.

It should be appreciated that the database 10 depicted herein includes,but is not limited to, RAM, cache memory, flash memory, magnetic disks,optical disks, removable disks, SCSI disks, IDE hard drives, tape drivesand all other types of data storage devices (and combinations thereof,such as RAID devices) generally known to those skilled in the art. Itshould further be appreciated that the characterization application 12,as depicted and discussed herein, may exist as a single application oras multiple applications, locally and/or remotely stored. It should alsobe appreciated that the number and location of the components depictedin FIG. 1 do not limit a typical imaging system 2 but are merelyprovided to illustrate a typical imaging system 2. Thus, for example, acomputing device 8 having a plurality of databases 10 or a remotelylocated characterization application 12 (either in part or in whole) orany combination of these may also be found in a typical imaging system2.

In one embodiment of a typical imaging system 2, the characterizationapplication 12 is adapted to receive and store characterization data(e.g., tissue type, etc.). The characterization data was determinedprior to using the tissue—characterization system 2 as follows. After aspecimen vascular object has been interrogated (e.g., IVUS data has beencollected), a histology correlation is prepared. In other words, thespecimen vascular object is dissected or cross-sectioned for histology.In one method of producing characterization data, the cross-section ispreviously marked, for example with a suture, so that the histology canbe corresponded to a portion of the IVUS image. The cross-section isthen prepared with a fixing and staining process that is well known inthe art. The staining process allows a clinician to identify a tissuetype(s), or a chemical(s) found within (e.g., a chemical correspondingto a particular tissue type, etc.). The identified tissue type or typesis then correlated to the IVUS data as will be explained below.

Where the imaging system 2 is or includes an OCT system, the imagingsystem 2 typically includes a light source 20 that produces light of adesired frequency and with other desired characteristics well understoodin the art that is ultimately directed from the catheter 6 to thepatient's vasculature by distal optics 22. A typical OCT imaging system2 has the light source 20 located remotely from or nearby the catheter6. Optical fibers 24 carry the light from the light source 20 to thedistal optics 22.

It should be appreciated that there may be many methods used to identifyor characterize the cross-sectional object as is well understood in theart besides the method just described. Thus, anyidentification/characterization method generally known to those skilledin the art may be used to characterize tissue. The identified tissuetype or characterization (i.e., characterization data) is then providedto the characterization application 12. In one embodiment, as shown inFIG. 1, the characterization data is provided via an input device 18electrically connected to the computing device 8. The characterizationdata is preferably then stored in the database 10. It should beappreciated that the input device depicted herein includes, but is notlimited to, a keyboard, a mouse, a scanner and all other data-gatheringand/or data-entry devices generally known to those skilled in the art.It should further be appreciated that the term tissue type orcharacterization, as these terms are used herein, include, but are notlimited to, fibrous tissues, fibro-lipidic tissues, calcified necrotictissues, necrotic core, calcific tissues, collagen compositions,cholesterol, thrombus, compositional structures (e.g., the lumen, thevessel wall, the medial-adventitial boundary, etc.) and all otheridentifiable characteristics generally known to those skilled in theart.

In one method of characterizing tissue, the characterization applicationis adapted to create a histology image and to identify at least onecorresponding region on an IVUS image. Specifically, digitized data isprovided to the characterization application (e.g., via the input device18), where the digitized data corresponds to the cross-sectionedvascular object. The digitized data is then used to create a histologyimage (i.e., a digital image or outline that substantially correspondsto the vascular object). A region of interest (ROI) on the histologyimage can then be identified by the operator. Preferably, the ROI ischaracterized by the characterization data, as previously provided, andmay be the entire histology image or a portion thereof. Thecharacterization application is then adapted to identify a correspondingregion (e.g., x,y coordinates, etc.) on the IVUS image.

In view of the foregoing, what is needed is an effective method anddevice for assisting a healthcare provider to identify patients whoseMS, or MS symptoms, are likely exacerbated if not caused, at least inpart, by blockages of one or more of the patient's internal jugularveins (IJV) or azygous veins (AZV) and for those patients, methods anddevices for applying one or more therapies to the blockages in thepatient's IJV or AZV veins.

SUMMARY

Methods and devices are disclosed that, in various embodiments andpermutations and combinations of inventions, diagnose and treat MS or MSsymptoms. In one series of embodiments, the invention consists ofmethods and devices for identifying patients whose MS, or MS symptoms,are likely exacerbated if not caused, at least in part, by blockages ofone or more of the patient's internal jugular veins (UV) or azygousveins (AZV). In preferred embodiments of the diagnostic methods, thestenoses in the patient's affected veins are identified. In otherembodiments of the present diagnostic methods, the nature of suchlesions and whether there is a significant disruption of blood pressureor flow, or both, is ascertained.

In another series of embodiments, the invention consists of methods anddevices for applying one or more therapies to the blockages in thepatient's IJV or AZV veins. In preferred embodiments of such methods anddevices, therapy is delivered to open the stenosis causing suchblockages.

It is an object of this invention in one or more embodiments to identifyblockages of a patient's vasculature or flow limiting or interruptingstructures that have likely exacerbated if not caused, at least in part,MS, or MS symptoms, in that patient.

It is an object of this invention in one or more embodiments to treatblockages of a patient's vasculature or flow limiting or interruptingstructures that have likely exacerbated if not caused, at least in part,MS, or MS symptoms, in that patient.

The invention will be described hereafter in detail with particularreference to the drawings. Throughout this description, like elements,in whatever embodiment described, refer to common elements whereverreferred to and referenced by the same reference number. Thecharacteristics, attributes, functions, interrelations ascribed to aparticular element in one location apply to that element when referredto by the same reference number in another location unless specificallystated otherwise.

BRIEF DESCRIPTIONS OF THE DRAWINGS

FIG. 1 is a schematic view of a typical intravascular ultrasound (IVUS)imaging system.

FIG. 2 is a schematic view of a typical intravascular optical coherencetomography (OCT) imaging system.

FIG. 3 is a flow chart of an embodiment of the diagnostic method of thepresent invention.

FIG. 4 is a flow chart of another embodiment of the diagnostic method ofthe present invention.

FIG. 5 is a flow chart of another embodiment of the diagnostic method ofthe present invention.

FIG. 6 is a flow chart of another embodiment of the diagnostic method ofthe present invention.

FIG. 7 is a schematic view of an embodiment of the diagnostic device ofthe present invention.

FIG. 8 is a flow chart of an embodiment of the therapeutic method of thepresent invention.

FIG. 9 is a flow chart of an alternate embodiment of the therapeuticmethod of the present invention.

FIG. 10 is a flow chart of an embodiment of the therapy delivered as thetherapeutic method of the present invention.

FIG. 11 is a side cross-sectional schematic view of a device of atherapy that could be applied as the therapy of the any of thetherapeutic methods of the present invention.

FIG. 12 is a side cross-sectional schematic view of a device of atherapy that could be applied as the therapy of the any of thetherapeutic methods of the present invention.

FIG. 13 is an end schematic view of the device of FIG. 12.

FIG. 14 is a side cross-sectional schematic view of a device of atherapy that could be applied as the therapy of the any of thetherapeutic methods of the present invention.

FIG. 15 is a side cross-sectional schematic view of an alternateembodiment of the device of FIG. 14.

FIG. 16 is a side cross-sectional schematic view of a device of atherapy that could be applied as the therapy of the any of thetherapeutic methods of the present invention.

FIG. 17 is a schematic view of an embodiment of the therapeutic deviceof the present invention.

FIG. 18 is a flow chart of another embodiment of the therapeutic methodof the present invention.

FIG. 19 is a flow chart of another embodiment of the therapeutic methodof the present invention.

FIG. 20 is a flow chart of another embodiment of the therapeutic methodof the present invention.

FIG. 21 is a flow chart of another embodiment of the therapeutic methodof the present invention.

FIG. 22 is a flow chart of another embodiment of the therapeutic methodof the present invention.

DETAILED DESCRIPTION

The present invention includes several embodiments. In particular, thepresent invention includes a Multiple Sclerosis Diagnostic Method 26,its corresponding Multiple Sclerosis Diagnostic Device 28, a MultipleSclerosis Treatment Diagnostic and Treatment Method 30 and itscorresponding Multiple Sclerosis Treatment Diagnostic and TreatmentDevice 32. The diagnostic method 26 and diagnostic device 28 determinewhether a patient's physiology indicates that the patient has a form ofMS, or MS symptoms, that are exacerbated if not caused, at least inpart, by blockages or flow limiting or interrupting structures of one ormore of the patient's internal jugular veins (IJV) or azygous veins(AZV). The therapeutic method 30 and therapeutic device 32 provide oneor more therapies to treat the patient's MS, or MS symptoms. Inembodiments of the invention, the therapeutic method 30 includes adiagnostic method 26 and, in addition, applies a therapy to treat theMS, or MS symptoms. In other embodiments of the invention, thetherapeutic device 32 includes a diagnostic device 28 that, in addition,also applies a therapy to treat the MS, or MS symptoms. Examples of flowlimiting or interrupting structures include, but are not limited to,physiological defects, stenoses and faulty valves.

Referring to the Figures, the diagnostic method is shown in the Figuresgenerally referred to by the reference number 26. The diagnostic method26, in preferred embodiments described hereafter, acts according toalgorithms having the following steps, as set out in the flow charts ofFIGS. 3-6.

In the diagnostic method 26 shown in FIG. 3, the diagnostic methodbegins at step 36 where venous outflow obstruction sites are identified.A preferred method of identifying these obstruction sites is bysequentially accessing the AZV entry into the superior vena cava and thetwo Common Jugular veins by selective venography at each of these sitesto confirm or exclude a significant stenosis or flow disruption.Venography, which is also called phlebography, involves taking an x-rayof the veins, a venogram, after a special dye is injected via a catheterinto the vein of interest. Typically, the dye is injected constantly viaa catheter. As a result, a venography is an invasive procedure.

Although venography has been a preferred method for selecting siteshaving significant stenosis or flow disruption, ultrasonography,including duplex ultrasonography, could also be used in the alternativeor in addition to identify obstructed outflow sites.

Ultrasonography incorporates two elements:

-   -   1) Grayscale Ultrasound (e.g., from an IVUS imaging system 2) is        used to visualize the structure or architecture of the vein to        identify stenoses (cross-sectional narrowing of the vein);    -   2) Color-Doppler ultrasound imaging (e.g., from Volcano        Corporation) is then used to visualize the flow or movement of a        blood within the vein;

and typically presents both displays on the same screen (“duplex”) tofacilitate interpretation. Where ultrasonography is used, a stenosishaving cross-sectional narrowing greater than about 70% is consideredworthy of treatment as are blood flow velocities greater than 250 cm/sec(which also indicate a region of narrowing or resistance produced by amajor stenosis). Ultrasonography can also be enhanced by tissuecharacterization such as the virtual histology characterizationdescribed above, for example, as part of the s5i™ Imaging System with VHcapability sold by Volcano Corporation of San Diego, Calif.

Besides venography and ultrasonography, transcutaneous echographyapplied to an accessible section of the IJV could also be used toidentify venous outflow obstruction sites and to confirm or exclude asignificant stenosis or flow disruption at those sites. Further, in anembodiment of the invention, radionuclides that bind to proteinsspecific to fibrin, such as radionuclides bound to insulin-like growthfactor (IGF) binding proteins (IGFBPs) are applied intravenously,preferably near where an obstruction is believed to be located, ororally. Then, external detectors such as gamma cameras capture and formimages from the detected radiation emitted by the radionuclides that arebound to the proteins of the fibrin. This allows the areas of venousoutflow obstruction caused by the buildup of thrombus to be located andto confirm or exclude a significant stenosis or flow disruption at thesite. These last two methods have the desirable characteristic of beingnon-invasive.

In a modification of the invention above where something is bound toproteins specific to fibrin, plasmin, other plasmids or any likesubstance that dissolves fibrin is bound to the same IGFBP that containsthe radionuclide or to an entirely different IGFBP and then delivered tothe site of the fibrin as described above. The plasmin, plasmid or othersubstance that dissolves fibrin in whatever form may be self-activated(i.e., it is active upon delivery) or may be activated by the exposureto either a specific light frequency or by ultrasound at a specificfrequency or any like energy source delivered either intravascularly ornoninvasively. Where these substances are active by a specific lightfrequency or by ultrasound at a specific frequency, the light orultrasound or both may be delivered via the distal optics 22 ortransducer 14, respectively.

Once the venous outflow obstruction sites have been identified bywhatever method, the method passes to step 38. In step 38, the nature ofthe stenotic lesion is assessed. This assessment is preferablyaccomplished by applying an imaging system 2 such as an IVUS or OCTsystem or a system having both IVUS and OCT or applying both IVUS andOCT imaging to suspected areas of narrowing or flow disruption toidentify intraluminal abnormalities including webs, flaps, inverted orincompetent valves and membranes as well as stenoses caused by plaque orthe buildup of fibrin or thrombus. Here, a significant stenosis, ofwhatever kind, is defined as luminal reduction greater than 50% of thenormal venous diameter near the stenosis as obtained during step 36 or asignificant flow disruption associated with an intraluminal abnormalitynoted during the IVUS or OCT imaging of this step 38. Both IVUS and OCTwill provide vessel information whereby vessel circumferencemeasurements can be made. This will allow the physician to check thelumen narrowing to determine whether such narrowing is significant asdefined above (i.e., cross-sectional narrowing greater than about 70% orblood flow velocities greater than 250 cm/sec). In a preferredembodiment of the invention, software is provided on the imaging system2 to correlate these measurements. Once IVUS or OCT or both IVUS and OCThas been used to assess the nature of the stenotic lesion, the methodpasses to step 40.

In step 40, the pressure gradient across the stenosis (as compared tothe superior vena cava) is determined. This pressure gradient ispreferably determined using either a manometer, pressure wire or anyother blood pressure measuring device if the suspected significantvenous stenosis/intraluminal abnormality is confirmed by any of themethods of step 38. Examples of pressure wires are the PrimeWirePRESTIGE™ guide wire, PrimeWire® guide wire and the ComboWire® XT guidewire all made and sold by Volcano Corporation of San Diego, Calif. Apressure gradient larger than 1-2 mm Hg may indicate the presence of asignificant stenosis. Information on the pressure gradient is preferablybut not required to be communicated to the healthcare provider. Thecommunication in this step 40 may take the form of a message displayedon console 4, the modifying of an image of a vascular structuredisplayed on the console 4 such as by appending a text or colorindicator that the patient's physiology at that location on the vesselis such that the patient's pressure gradient exceeds the targetedamount, the communication of the parameter values themselves separatelyor by any other means well within the skill of one skilled in the art tocommunicate such values.

In the diagnostic method 26 described above, the listed steps 36-40 wereperformed in the order given. However, it is within the scope of theinvention for steps 38 and 40 to be reversed. In this embodiment of theinvention shown in FIG. 4, the diagnostic method 26 has the form of thesteps above performed in the following sequential order:

-   -   Step 36: Indentify venous outflow obstruction sites;    -   Step 40: Determine pressure gradient across the stenosis; and    -   Step 38: Assess the nature of the stenotic lesion.

Further, in another embodiment of the diagnostic method 26, the methodshown in FIG. 3 could be simplified so that either step 38 or step 40 isdone without doing the other so that the method takes the followingforms, shown in FIGS. 5 and 6, respectively, of the steps aboveperformed in the following sequential order:

-   -   Step 36: Indentify venous outflow obstruction sites; and    -   Step 38: Assess the nature of the stenotic lesion.        and,    -   Step 36: Indentify venous outflow obstruction sites; and    -   Step 40: Determine pressure gradient across the stenosis.

As mentioned above, the diagnostic method 26 in all forms assesseswhether a patient has a form of MS, or MS symptoms, that are likelyamenable to treatment by a therapy that is directed to the stenosis inthe patient's vein and, as a result, has diagnostic value as adiagnostic tool. This diagnostic value occurs in all the embodiments ofthe diagnostic method 26 described above.

The diagnostic method 26 is typically run as software on a computingdevice 8 and thus the combination of the computing device 8 and thediagnostic methods 20, as described above, becomes the diagnostic device28. FIG. 7 shows an embodiment of the diagnostic device 28 where thesteps 36-38 are performed on the computing device 8. Although thediagnostic device 28 is preferably operated on a computing device 8, thediagnostic device 28 may also be operated separately on any systemhaving sufficient computing capability to perform the steps of thediagnostic method 26 and be operatively connected to the console 4,computing device 8, characterization application 12 or database 10 orany combination of these. In addition, the diagnostic device 28 may alsobe an application specific device or hardwired specifically to performthe functions described herein.

The diagnostic device 28, in preferred embodiments, acts according toalgorithms described above in connection with the diagnostic method 26.The diagnostic device 28 may be implemented on or may be an adjunct toan imaging system 2. The imaging system 2 may take the form of anintravascular ultrasound (IVUS) imaging system 2 as described aboveincluding a console 4, IVUS catheter 6, a computing device 8 comprisinga database 10 and a characterization application 12 electricallyconnected to the database 10 and typically run on the computing device8. Alternately or in addition, the imaging system 2 may take the form ofan optical coherence tomography (OCT) system that also includes aconsole 4, OCT catheter 6, a computing device 8 comprising a database 10and a characterization application 12 electrically connected to thedatabase 10 and typically run on the computing device 8.

Although IVUS and OCT systems singly or in combination have beendescribed as the imaging system 2, any imaging system that obtainsimages of the patient's vascular may be used. Such alternate imagingsystems 2 will also typically include a console 4, a catheter 6appropriate for that imaging system 2, a computing device 8 comprising adatabase 10 and a characterization application 12 electrically connectedto the database 10 and typically run on the computing device 8.Regardless of the imaging system 2, the diagnostic device 28 is adaptedto communicate, that is both receive and transmit data and information,with the console 4 or the computing device 8.

Where it has been determined that a patient has a form of MS, or MSsymptoms, that are likely amenable to treatment by a therapy that isdirected to the stenosis in the patient's vein, it is also desirable tohave a tool that, under the physician's control, directs a desiredtherapy to the stenosis. The therapeutic method 30 and its correspondingtherapeutic device 32, as described hereafter, is such a tool.

In one embodiment of the therapeutic method 30 shown in FIG. 8, thediagnostic method 26 is included as a diagnostic precursor to applying adesired therapy. So, the therapeutic method 30 in a preferred embodimentincludes a diagnostic method 26 that operates as described above in allthe variants of diagnostic method 26. In another embodiment of thetherapeutic method 30 shown in FIG. 9, the therapeutic method 30 doesnot include a diagnostic method 26 but includes only the delivery of atherapy 42 as will be described hereafter.

In the embodiment of the therapeutic method 30 of FIG. 8 including adiagnostic method 26, after the diagnostic steps have been accomplishedand it has been determined that a patient's physiology indicates thatthe patient has a form of MS, or MS symptoms, that are exacerbated ifnot caused, at least in part, by blockages of one or more of thepatient's internal jugular veins (IJV) or azygous veins (AZV), theprogram passes to step 42. In step 42, a desired therapy is applied totreat the stenotic lesion. The therapy applied is preferably one that,as a result of the application of the therapy, produces a reduction ofthe stenosis such that the residual stenosis no longer is flow limitingor that a pressure gradient exceeding 1-2 mm Hg is no longer observed orboth.

In one embodiment of the therapeutic method 30, a preferred therapy instep 42 is angioplasty to open or enlarge the troubling stenosis. Theangioplasty may be either conventional angioplasty or angioplasty usinga cutting or scoring balloon. FIG. 10 shows a flow chart of the stepsinvolved in the therapeutic method 30 to accomplish such an angioplastyprocedure. The goal of the angioplasty procedure will be to restore thevenous outflow structure to where it is no longer flow limiting, flowdisruption is resolved and pressure gradient is minimal.

In FIG. 10, the angioplasty therapy is begun at step 44 where theappropriate angioplasty balloon to be used is determined based onmeasurements previously made such as during a venogram. It is preferablebut not required for the balloon to be a non-compliant balloon that willhave a nominal inflated diameter of at least 80% of the normal proximalnon-stenosed vein. The benefit of using a non-compliant balloon here isto obtain high pressure to increase the opportunity for compression ofthe obstruction.

The balloon is preferably a one piece balloon. Such a balloon may, butis not required to be, coated with or exuding a drug such as tissueplasminogen activator, urokinase, streptokinase, collagenace, hepranoidsand any other fibrinolytic or direct anti-thrombin drug or drugs orantigens or both that may promote more rapid healing of a vessel.

Further, as mentioned above, the balloon may be a cutting or scoringballoon. A cutting balloon is one that has small blades that areactivated (moved outward) by actuation of the balloon. The cuttingblades score the fibrin of a lesion, particularly thrombus that isattached to and incorporated into the vein wall, thereby creating spacethat allows the rest of the fibrin to be compressed into a largeropening by the opening of the balloon. When the appropriate balloon tobe used to open the stenosis has been determined, by whatever means, theprogram then passes to step 46. The scoring balloon is one that scoresthe plaque circumferentially to dilate the obstructed vessel such as theAngioSculpt Scoring Balloon Catheter made and sold by AngioScore Inc. ofFremont, Calif.

At step 46, the patient is loaded with intravenous weight based load ofheparin (50-100 U/kg) to confirm an Activated Clotting Time (ACT) of atleast 250 as is well understood in the art. After loading the patientwith heparin to confirm ACT, the program then passes to step 48.

In step 48, the balloon is placed at the stenosis and inflated as iswell understood in the art. After confirmation of the ACT, an exchangelength 0.035″ exchange length glide wire is advanced into the proximalvein of interest (before the obstruction) and the non-compliant balloonis placed across the stenosis. The balloon is slowly inflated, forexample, with one atmosphere per 30 seconds until reaching nominalpressure (e.g., 8-12 atmospheres) to open the stenosis. The dilatedballoon is left in place for a clinically significant time as is wellunderstood in the art. After the balloon has been left in place for aclinically significant time, the method then passes to step 50.

In step 50, the balloon is deflated and withdrawn. The balloon ispreferably deflated at a moderate rate (e.g., one atmosphere per 15seconds) and then withdrawn from the patient's vascular by techniqueswell understood in the art.

FIG. 11 shows a device of another therapy that could be applied as thetherapy in step 42. In this embodiment of the therapeutic method 30, anocclusive balloon is shown generally labeled 46. The balloon catheter 52has a catheter body 54 with a distal end 56, an ultimate distal end 58,a proximal end 60, a central lumen 62, a balloon 64 and a balloon lumen66. The balloon 64 is located a small distance from the ultimate distalend 58 and the central lumen 62 extends from the proximal end of theballoon catheter 52 to the ultimate distal end 58.

The balloon catheter 52 also has an imaging transducer 14 located at thedistal end 56 of the balloon catheter 52. The imaging transducer 14 ispreferably an IVUS or OCT imaging transducer that is part of an imagingsystem 2 such as has been described above that allows the user toidentify intravascular stenoses. The imaging system 2 may also includeso-called virtual histology (VH) technology to help the physicianrecognize and identify the morphology of tissue, particularly plaqueassociated with a lesion, in vivo (i.e., the location and composition ofplaque in the patient's body). The following systems for detecting andcharacterizing plaque using IVUS with VH are disclosed in U.S. Pat. Nos.6,200,268 entitled “VASCULAR PLAQUE CHARACTERIZATION” issued Mar. 13,2001 with D. Geoffrey Vince, Barry D. Kuban and Anuja Nair as inventors,6,381,350 entitled “INTRAVASCULAR ULTRASONIC ANALYSIS USING ACTIVECONTOUR METHOD AND SYSTEM” issued Apr. 30, 2002 with Jon D.Klingensmith, D. Geoffrey Vince and Raj Shekhar as inventors, 7,074,188entitled “SYSTEM AND METHOD OF CHARACTERIZING VASCULAR TISSUE” issuedJul. 11, 2006 with Anuja Nair, D. Geoffrey Vince, Jon D. Klingensmithand Barry D. Kuban as inventors, 7,175,597 entitled “NON-INVASIVE TISSUECHARACTERIZATION SYSTEM AND METHOD” issued Feb. 13, 2007 with D.Geoffrey Vince, Anuja Nair and Jon D. Klingensmith as inventors,7,215,802 entitled “SYSTEM AND METHOD FOR VASCULAR BORDER DETECTION”issued May 8, 2007 with Jon D. Klingensmith, Anuja Nair, Barry D. Kubanand D. Geoffrey Vince as inventors, 7,359,554 entitled “SYSTEM ANDMETHOD FOR IDENTIFYING A VASCULAR BORDER” issued Apr. 15, 2008 with JonD. Klingensmith, D. Geoffrey Vince, Anuja Nair and Barry D. Kuban asinventors and 7,463,759 entitled “SYSTEM AND METHOD FOR VASCULAR BORDERDETECTION” issued Dec. 9, 2008 with Jon D. Klingensmith, Anuja Nair,Barry D. Kuban and D. Geoffrey Vince, as inventors, the teachings ofwhich are hereby incorporated by reference herein in their entirety.

In one embodiment of the present invention, a characterizationapplication of the IVUS system is adapted to receive and store venouscharacterization data (e.g., tissue type, etc.) that is subsequentlyutilized to classify the tissue type of a patient. For example, after avenous vessel has been interrogated (e.g., IVUS data has beencollected), a histology correlation is prepared. In other words, thevenous vessel is dissected or cross-sectioned for histology. In oneembodiment of the present invention, the cross-section is marked, forexample with one or more sutures, so that the histology can becorrelated to a portion of the IVUS image based on the marker(s). Thecross-section is then prepared with a fixing and staining process thatis well known in the art. The staining process allows a trainedclinician to identify a tissue type(s), or a chemical(s) found within(e.g., a chemical corresponding to a particular tissue type, etc.). Itshould be appreciated that the particular method used to identify orcharacterize the cross-sectional venous vessel is not a limitation ofthe present invention. Thus, all identification/characterization methodsgenerally known to those skilled in the art are within the spirit andscope of the present invention.

The identified tissue type or characterization (i.e., characterizationdata) is then provided to the characterization application for storageand access in future procedures. Accordingly, in some instances thecharacterization data is stored in a venous tissue characteristicdatabase. It should be appreciated that the data may input to thecharacterization application and/or database using any suitable inputdevice(s) generally known to those skilled in the art. It should furtherbe appreciated that the term tissue type or characterization, as theseterms are used herein, include, but are not limited to, fibrous tissues,fibro-lipidic tissues, calcified necrotic tissues, calcific tissues,collagen compositions, cholesterol, thrombus, compositional structures(e.g., the lumen, the vessel wall, the medial-adventitial boundary,etc.) and all other identifiable characteristics generally known tothose skilled in the art.

One method of populating the venous tissue characteristic databasebegins with collecting IVUS data (i.e., RF backscatter data) from aportion of a venous vessel. This data is then used to create an IVUSimage at step. The interrogated portion of the venous vessel iscross-sectioned and a tissue type (or a characterization thereof) isidentified. This information (i.e., characterization data) is thentransmitted to a computing device (or the equivalent thereof). An imageof the cross-sectioned vascular object is created and at least oneregion of interest is identified (e.g., by an operator). This image isthen morphed, if needed, to substantially match it to the initiallyobtained IVUS image. This may include identifying at least one landmarkand applying at least one algorithm (e.g., a morphometric algorithm, athin plate spline deformation technique, etc.). The region(s) ofinterest is mapped to the IVUS image and associated IVUS data isidentified. Spectral analysis is then performed on the associated IVUSdata, and at least one parameter is identified. The at least oneparameter and the characterization data are then stored in the database.In one embodiment of the present invention, the at least one parameteris stored such that it is linked to the characterization data. It shouldbe appreciated that the order in which these steps are presented is notintended to limit the present invention. Thus, for example, creating anIVUS image after the vascular object is cross-sectioned is within thespirit and scope of the present invention.

The above-described process is repeated for each tissue componentdesired to be identified and repeated for each component as many timesas desired in order to obtain a more accurate range of signalproperties. With the database populated, a tissue type or characteristiccan be automatically and accurately identified if the acquiredparameters substantially match parameters stored in the database. Withthe venous tissue characteristic database populated, thecharacterization application of the IVUS system can then be utilized toreceive IVUS data, determine parameters related thereto, and use thevenous tissue characteristic parameters stored in the database (i.e.,histology data) to identify tissue type(s) or characterization(s)thereof.

The central lumen 62 of the balloon catheter 52 is attached to a sourceof suction (not shown) at the proximal end 60 of the balloon catheter 52by means well understood in the art. The distal end 56 of the ballooncatheter 52 is advanced in the patient's vein of interest past thelesion but where the balloon 64 is downstream of the lesion. The balloon64 is inflated so that it occludes blood flow in the vein. In thisconfiguration, the ultimate distal end 58 is located near the lesion.The suction is activates so that suction is applied at the ultimatedistal end 58. Because the ultimate distal end 58 is located in closeproximity of the lesion, thrombus will be subject to the suction forceand sucked into the balloon catheter to travel through the central lumen62 to be removed through the proximal end 60.

Another embodiment of a device of another therapy that could be appliedas the therapy in step 42 is shown in FIGS. 12 and 13. In thisembodiment, a cutting catheter 68 is shown. The cutting catheter 68 hasa catheter body 70 with a distal end 72, a proximal end 74, a centrallumen 76 through which a guide wire (not shown) may be passed and anouter surface 78. The cutting catheter 68 includes, but is not limitedto, the types disclosed in U.S. Pat. Nos. 5,421,338 entitled “AcousticImaging Catheter and the Like” issued to Robert J. Crowley, Mark A. Hammand Charles D. Lennox on Jun. 6, 1995; 6,283,921 entitled “UltrasonicVisualization and Catheters Therefor” issued to Elvin Leonard Nix, AmitKumar Som, Martin Terry Rothman and Andrew Robert Pacey on Sep. 4, 2001;5,800,450 entitled “Neovascularization Catheter’ issued to Banning GrayLary and Herbert R. Radisch, Jr. on Sep. 1, 1998; 5,507,761 and5,512,044 both entitled “Embolic Cutting Catheter” issued to Edward Y.Duer on Apr. 16, 1996 and Apr. 30, 1996, respectively; 5,925,055entitled “Multimodal Rotary Abrasion and Acoustic Ablation Catheter”issued to Sorin Adrian and Paul Walinsky on Jul. 20, 1999; 4,917,085entitled “Drive Cutting Catheter Having a New and Improved Motor” issuedto Kevin W. Smith on Apr. 17, 1990 and US Published Patent ApplicationNo. 2006111704 entitled “Devices, Systems, and Methods for EnergyAssisted Arterio-venous Fistula Creation” filed by Rodney Brenneman,Dean A. Schaefer and J. Christopher Flaherty on Nov. 16, 2005, theteachings of which are incorporated herein in their entirety byreference.

The cutting catheter 68 preferably has an imaging transducer 14 as partof an imaging system 2 located at its distal end 72. Further, thecutting catheter 68 includes cutting blades 80 located on its outersurface 78 near the distal end 72. The cutting blades 80 are preferablyanywhere from about 0.5-2 mm in depth and from about 5-20 mm in lengthalthough other lengths can be used depending on the vessel that thecutting catheter 68 will be used in. The cutting blades 80 can be spacedradially around the outer surface 78 for cutting or scoringcircumferentially or can be spaced on one side of the catheter 68 forselective cutting or scoring. When the catheter 68 is pulled back duringan imaging procedure, the cutting blades 80 contact and score the fibrinof the lesion, particularly thrombus that is attached to andincorporated into the vein wall, thereby creating space that allows therest of the fibrin to be compressed into a larger opening by the openingof the balloon.

Yet another embodiment of a device of another therapy that could beapplied as the therapy in step 42 is shown in FIG. 14. In thisembodiment, an ablation catheter 82 is shown. Such ablation catheter 82delivers ablation energy through laser, so-called Radio FrequencyAblation or “RFA”, both ablative and thermal, cryoablation, ultrasound,microwave or other energy sources. Examples of such ablation catheters80 include, but are not limited to, those disclosed in U.S. Pat. Nos.6,245,066 entitled “Ablation Catheter” issued to John Mark Morgan andAndrew David Cunningham on Jun. 12, 2001; 5,267,954 entitled“Ultra-sound catheter for removing obstructions from tubular anatomicalstructures such as blood vessels” issued to Henry Nita on Dec. 7, 1993;6,325,797 entitled “Ablation Catheter and Method for Isolating aPulmonary Vein” issued to Mark T. Stewart, William J. Flickinger, DavidE. Franscischelli, Rahul Mehra and Xiaoyi Min on Dec. 4, 2001; 6,203,537entitled “Laser-driven Acoustic Ablation Catheter” issued to SorinAdrian on Mar. 20, 2001; 5,427,118 entitled “Ultrasonic Guidewire”issued to John H. Wang, Henry Nita, Timothy C. Mills, and Douglas H.Gesswin on Jun. 27, 1995; 6,701,176 entitled “Magnetic-resonance-guidedimaging, electrophysiology, and ablation” issued to Henry R. Halperin,Ronald D. Berger, Ergin Atalar, Elliot R. McVeigh, Albert Lardo, HughCalkins and Joao Lima on Mar. 2, 2004; 6,231,518 entitled“Intrapericardial electrophysiological procedures” issued to James R.Grabek, Carl M. Beaurline, Cecil C. Schmidt, Lawrence A. Lundeen andPatricia J. Rieger on May 15, 2001; 6,949,094 entitled “MiniatureRefrigeration System for Cryothermal Ablation Catheter” issued to RanYaron on Sep. 27, 2005; 6,592,612 entitled “Method and apparatus forproviding heat exchange within a catheter body” issued to WilfredSamson, Hoa Nguyen, Mike Lee, Brady Esch, Eric Olsen and Jeff Valko onJul. 15, 2003; 7,291,146 entitled “Selectable Eccentric Remodelingand/or Ablation of Atherosclerotic Material” issued to Tom A. Steinke,Corbett W. Stone, Stephen O. Ross, Brian S. Kelleher, Raphael M. Micheland Donald H. Koenig on Nov. 6, 2007; 7,742,795 entitled “Tuned RFenergy for Selective Treatment of Atheroma and Other Target Tissuesand/or Structures” issued to Corbett W. Stone, Michael F. Hoey, Tom A.Steinke, Raphael M. Michel and Arthur G. Blanck on Jun. 22, 2010; USPublished Patent Application Nos. 2003092995 entitled “System and methodof positioning implantable medical devices” filed by David L. Thompsonon Feb. 28, 2002; 2006184048 entitled “Tissue Visualization andManipulation System” filed by Vahid Saadat on Oct. 25, 2005; 2010256616entitled “Recanalizing Occluded Vessels Using Radiofrequency Energy”filed by Osamu Katoh and Wayne Ogata on Apr. 2, 2010, 2008262489entitled “Thrombus Removal” and filed by Tom A. Steinke on Apr. 23,2008; 2008125772 entitled “Tuned RF Energy and Electrical TissueCharacterization for Selective Treatment of Target Tissues” filed byCorbett W. Stone, Michael F. Hoey, Tom A. Steinke, Raphael M. Michel,Arthur G. Blanck, Marlene Kay Truesdale and Bret Herscher on Oct. 18,2007 and 2010125268 entitled “Selective Accumulation of Energy With orWithout Knowledge of Tissue Topography” filed by Rolfe Tyson Gustus,Linas Kunstmanas and Arthur G. Blanck on Nov. 12, 2009 and WIPOPublished Patent Application No. WO03073950 entitled “Optical FibreCatheter for Thermal Ablation” filed by Andrea Venturelli on Jan. 27,2003, the teachings of which are incorporated by reference herein intheir entirety. Further examples of RF ablation systems include, but arenot limited to ablative systems such as that sold by Halt Medical Inc.of Livermore, Calif. that use the heat energy of radio frequency wavesto ablate tissue, those sold by Covidien plc through its Valleylab brandin Boulder, Colo. and the VNUS® RF (radiofrequency) Ablation system soldby AngioDynamics of Latham, N.Y.

The ablation catheter 82 has a catheter body 84 with a distal end 86, aproximal end 88, a central lumen 90 through which a guide wire (notshown) may be passed, an outer surface 92 and ablation system 94. Theablation catheter 82 preferably has, but is not required to have, animaging transducer 14 as part of an imaging system 2 located at itsdistal end 86. As the ablation catheter 82 is advanced to the site ofthe lesion, the imaging system 2, if present, helps the physician tolocate the lesion. Once the ablation catheter 82 is located at thelesion, the ablation therapy is applied by the ablation system 94 toablate the lesion. The imaging system 2 may be particularly useful inhelping the physician apply the ablation therapy and assess the extentof such ablation.

In an alternate embodiment of the device of FIG. 14 shown in FIG. 15,the imaging system 2 is an OCT system and ablation system 94 is combinedwith the distal optics 22 of the imaging system 2. In a variant of thisembodiment, the ablation provided by the ablation system 94 is laserablation that is supplied to the ablation system 94 from the same lightsource 20 used by the OCT system to produce the OCT images, typicallythrough optical fibers 24 connecting the light source 20 to the distaloptics 22. Although the light source 20 used to produce the OCT imageswould typically be located remotely from the distal optics 22 suppliedlight via the optical fibers 24, it is within the scope of the presentinvention in all embodiments for the light source 20 to be located inclose proximity to the distal optics 22. In a variant of this, this samelight source 20 provides not only the light needed to produce the OCTimages but also the laser light used by the ablation system 94 to do theablation.

Yet another embodiment of a device of another therapy that could beapplied as the therapy in step 42 is shown in FIG. 16. In thisembodiment, a therapeutic agent deliver catheter 96 is shown. Suchtherapeutic agent deliver catheter 96 delivers a therapeutic agent tothe lesion to dissolve fibrin or thrombus present at or causing thelesion or otherwise treat the lesion. Examples of such therapeutic agentdelivery catheters 92 include, but are not limited to, those disclosedin U.S. Pat. Nos. 5,135,516 entitled “Lubricious AntithrombogenicCatheters, Guidewires and Coatings” issued to Ronald Sahatjian and KurtAmplatz on Aug. 4, 1992; 6,535,764 entitled “Gastric treatment anddiagnosis device and method” issued to Mir A. Imran, Olivier K. Colliou,Ted W. Layman, Deepak R. Gandhi and Sharon L. Lake on Mar. 18, 2003;5,336,178 entitled “Intravascular Catheter with Infusion Array” issuedto Aaron V. Kaplan, James R. Kermode and Enrique J. Klein on Aug. 9,1994; 7,063,679 entitled “Intra-aortic Renal Delivery Catheter” issuedto Mark Maguire and Richard Geoffrion on Jun. 20, 2006; 7,292,885entitled “Mechanical Apparatus and Method for Dilating and Delivering aTherapeutic Agent to a site of Treatment” issued to Neal Scott andJerome Segal on Nov. 6, 2007; 6,179,809 entitled “Drug Delivery Catheterwith Tip Alignment” issued to Alexander Khairkhahan, Michael J.Horzewski, Stuart D. Harman, Richard L. Mueller and Douglas R.Murphy-Chutorian on Jan. 30, 2001; 5,419,777 entitled “Catheter forInjecting a Fluid or Medicine” issued to Berthold Hofling on May 30,1995; 6,733,474 entitled “Catheter for Tissue dilatation and drugDelivery” issued to Richard S. Kusleika on May 11, 2004; and 2010168714entitled “Therapeutic Agent Delivery System” filed by Jessica L. Burke,Grant T. Hoffman and Drew P. Lyons, Ellettsville, Ind. 1US) on Feb. 3,2010; 2010125238 entitled “Iontophoretic Therapeutic Agent DeliverySystem” filed by Whye-Kei Lye and Kareen Looi on Nov. 7, 2009;2003032936 entitled “Side-exit Catheter and Method for its Use” filed byRobert J. Lederman on Aug. 10, 2001, the teachings of which areincorporated by reference herein in their entirety. Examples oftherapeutic agents that may be delivered to the lesion include, but arenot limited to tissue plasminogen activator, urokinase, streptokinase,collagenace, hepranoids and any other fibrinolytic or directanti-thrombin drug. The therapeutic agent deliver catheter 96 has acatheter body 98 with a distal end 100, a proximal end 102, a centrallumen 104 through which a guide wire (not shown) may be passed, an outersurface 106, a balloon 108 and a balloon lumen 110. The therapeuticagent deliver catheter 96 preferably has, but is not required to have,an imaging transducer 14 as part of an imaging system 2 located at itsdistal end 100. The balloon 108 is inflated and deflated via the balloonlumen 110 as is well understood in the art.

The balloon 108 delivers the therapeutic agent. The therapeutic agentmay coat the balloon 108 so that as the balloon is inflated, thetherapeutic agent is brought into contact with a lesion so that thetherapeutic agent may be applied to the lesion. Alternately, the balloon108 may be porous or have slits or other fenestrations to allowtherapeutic agent present within the balloon to pass through the pores,slits or other fenestrations to come into contact with the tissue at ornear a stenosis. As the therapeutic agent deliver catheter 96 isadvanced to the site of the lesion, the imaging system 2, if present,helps the physician to locate the lesion. Once the therapeutic agentdeliver catheter 96 is located at the lesion, the therapeutic agent tois applied to the lesion as described above. The imaging system 2 may beparticularly useful in helping the physician apply the therapeutic agentand assess the extent of such therapy.

The therapeutic method 30 is also typically run as software on acomputing device 8 and thus the combination of the computing device 8and the therapeutic methods 24, as described above, becomes thetherapeutic device 32 (FIG. 17). Although the therapeutic device 32 ispreferably operated on a computing device 8, the therapeutic device 32may also be operated separately on any system having sufficientcomputing capability to perform the steps of the therapeutic method 30,and diagnostic method 26 if present, and be operatively to the console4, computing device 8, characterization application 12 or database 10 orany combination of these. In addition, the therapeutic device 32 mayalso be an application specific device or hardwired specifically toperform the functions described herein.

The therapeutic device 32, in preferred embodiments, acts according toalgorithms described above in connection with the therapeutic method 30.The therapeutic device 32 may be implemented on or may be an adjunct toan imaging system 2. The imaging system 2 may take the form of anintravascular ultrasound (IVUS) imaging system 2 as described aboveincluding a console 4, IVUS catheter 6, a computing device 8 comprisinga database 10 and a characterization application 12 electricallyconnected to the database 10 and typically run on the computing device8. Alternately or in addition, the imaging system 2 may take the form ofan optical coherence tomography (OCT) system that also includes aconsole 4, OCT catheter 6, a computing device 8 comprising a database 10and a characterization application 12 electrically connected to thedatabase 10 and typically run on the computing device 8.

In several embodiments of the invention described herein, the therapydelivery device 26 such as the balloon catheter 52, cutting catheter 68,ablation catheter 82 and therapeutic agent deliver catheter 96 includedan imaging transducer 14 as part of an imaging system 2 that allowed thetherapy delivery device to be located with respect to the lesion so thatthe therapy could be most effectively applied. In any of the therapydelivery systems described herein, it is preferable but not required butnot required to add an imaging transducer 14 as part of an imagingsystem 2, typically near the distal end of such therapy deliverydevices, to also allow the therapy delivery device to be located withrespect to the lesion so that the therapy can be most effectivelyapplied.

In any of the embodiments for administering a therapy described above,it may also be useful to apply embolic protection to prevent pieces offibrin, thrombus or other tissue dislodged by the application of therapyin step 42 from moving downstream with the blood flow. Since the primarytherapeutic application of the invention described herein is intended tobe applied to a patient's internal jugular veins (IJV) or azygous veins(AZV), such unwanted material will move with the blood downstream intothe patient's heart and ultimately into the patient's lungs where suchmaterial may cause an embolism. Consequently, the use of embolicprotection such as the SpiderFX® Embolic Protection Device made and soldby ev3, Inc. of Plymouth, Minn. and the FilterWire EZ™ EmbolicProtection System for SVG's made and sold by Boston Scientific, Inc. ofNatick, Mass. may help prevent the occurrence of such embolisms.

The therapeutic method 30 in another embodiment shown in FIG. 18includes a step 114 so that the program passes from step 42 to step 114.In step 114, intraluminal abnormalities are assessed to see if thetherapy of step 42 worked. A preferred way to assess the intraluminalabnormalities is to reintroduce the diagnostic catheter over the sameexchange wire used as part of the therapy of step 42 to perform apost-therapy selective venogram and assess the residual stenosis of thelesion.

In a variant of all the therapeutic methods 24, as shown in FIG. 19, itis desirable to assess the pressure gradient across the stenosis afterthe therapy of step 42 has been applied. Consequently, after step 42 hasbeen completed, the method passes to step 116. At step 116, the pressuregradient across the stenosis is assessed as described in step 38 todetermine, post-therapy, whether adequate blood flow is now present as aresult of the therapy of step 42.

Further, it may be desirable to assess the nature of the stenotic lesionpost-therapy. Consequently, in another embodiment of the therapeuticmethods 24, as shown in FIG. 20, this assessment of the nature of thestenotic lesion post-therapy is preferably accomplished as step 118 byapplying IVUS or OCT or both IVUS and OCT to the area of the appliedtherapy in step 42. As mentioned above, a significant stenosis isdefined as luminal reduction greater than 50% of normal venous diameteras obtained during step 36 or a significant flow disruption associatedwith an intraluminal abnormality noted during the IVUS or OCT imaging atstep 38. Consequently, a successful therapy occurs when the stenosis nowhas a luminal reduction less than 50% of normal venous diameter asobtained during step 36 with no significant flow disruption.

Although embodiments of the therapeutic method 30 have been describedabove in connection with a step 42 with may optionally include eitherstep 116 or 118, an alternate therapeutic method 30 may also includeboth step 116 and 118 performed in any order.

In addition, if the therapy of step 42 was not sufficient to provide thedesired blood flow or the desired reduction of the stenosis, in anadditional embodiment of the therapeutic method 30, additional therapyof any of the types described above may be applied as shown in FIG. 21.As mentioned above, the desired reduction of the stenosis is such thatthe residual stenosis is less than 75% of the normal proximal diameterof the stenotic vein or that a pressure gradient exceeding 1 mm Hg is nolonger observed. In this embodiment of the therapeutic method 30,additional therapy will be performed if these therapy goals are notobserved. Consequently, in this embodiment of the therapeutic method 30,if the therapy goals are not met, the program passes from step 42 tostep 120 where step 120 is the application of an additional therapy. Thetherapy of step 120 may be either the reapplication of the same therapythat was applied in step 42 or the application of an entirely newtherapy of the types described above. In this embodiment of thetherapeutic method 30, steps 114, 116 may also be applied as describedin connection with step 42 or applied singly or in combination to step120.

Further, as shown in FIG. 22, after either step 42 or step 120,additional therapy may also be performed at step 122 on all affectedveins using the same techniques described above in step 42 if there areadditional affected veins with significant stenoses in the IJV or AZV.Further, additional therapies or the reapplication of any of thetherapies listed above in connection with steps 42 and 120 may beapplied to these additional affected veins.

The present invention has been described in connection with manydifferent diagnostic and therapeutic methods and devices. The presentinvention also anticipates that more than one diagnostic method anddevice may be applied or combined into a single method or device.Likewise, the present invention also anticipates that more than onetherapeutic method and device may be applied or combined into a singlemethod or device. Further, various permutations and combinations ofdiagnostic and therapeutic devices may be combined together, each actingaccording to the descriptions above, into a single method or singledevice.

Although imaging systems 2 described herein have been eitherintravascular ultrasound (IVUS) systems or optical coherence tomography(OCT) systems, any other system capable of producing an image of apatient's vasculature may be used as the imaging system 2. Further,although the inventions described herein have been described as beingdirected to primarily to the diagnosis and treatment of MS, it is alsowithin the scope of the invention to be directed at diagnosing andtreating deep vein thrombosis (DVT) and pulmonary embolisms. To diagnoseand treat these maladies, the devices and methods described herein areplaced in the peripheral veins or pulmonary vessels, respectively,instead of in the IJV or AZV. For these maladies, embodiments of theinvention described herein that remove thrombus from the vessel wall maybe particularly useful.

The present invention has been described in connection with certainembodiments, combinations, configurations and relative dimensions. It isto be understood, however, that the description given herein has beengiven for the purpose of explaining and illustrating the invention andare not intended to limit the scope of the invention. In addition, it isclear than an almost infinite number of minor variations to the form andfunction of the disclosed invention could be made and also still bewithin the scope of the invention. Consequently, it is not intended thatthe invention be limited to the specific embodiments and variants of theinvention disclosed. It is to be further understood that changes andmodifications to the descriptions given herein will occur to thoseskilled in the art. Therefore, the scope of the invention should belimited only by the scope of the claims.

1. A Pulmonary Embolism diagnostic device comprising: a computing deviceconfigured to perform the steps of: identifying venous outflowobstruction sites in pulmonary vessels; assessing the nature of astenotic lesion associated with at least one of the identified venousoutflow obstruction sites in the pulmonary vessels; and determining thepressure gradient across the stenotic lesion as compared to the superiorvena cava.
 2. The device of claim 1 wherein the computing deviceincludes an imaging system selected from the group consisting of anintravascular ultrasound (IVUS) imaging system and an optical coherencetomography (OCT) system.
 3. The device of claim 1 wherein the step ofidentifying venous outflow obstruction sites in pulmonary vesselsincludes sequentially accessing pulmonary vessels by selectivevenography at each of these sites to confirm or exclude a significantstenosis or flow disruption.
 4. The device of claim 1 wherein the stepof identifying venous outflow obstruction sites includes usingultrasonography to identify obstructed outflow sites.
 5. The device ofclaim 4 wherein the step of identifying venous outflow obstruction sitesincludes using ultrasonography includes using duplex ultrasonography. 6.The device of claim 1 wherein the step of identifying venous outflowobstruction sites in pulmonary vessels includes both sequentiallyaccessing pulmonary vessels by selective venography at each of thesesites to confirm or exclude a significant stenosis or flow disruptionand using ultrasonography to identify obstructed outflow sites.
 7. Thedevice of claim 1 wherein the step of identifying venous outflowobstruction sites in pulmonary vessels includes using transcutaneousechography applied to an accessible section of a pulmonary vein toidentify venous outflow obstruction sites and to confirm or exclude asignificant stenosis or flow disruption at those sites.
 8. The device ofclaim 1 wherein the step of identifying venous outflow obstruction sitesincludes the steps of: a) applying radionuclides that bind to proteinsspecific to fibrin, such as radionuclides bound to insulin-like growthfactor (IGF) binding proteins (IGFBPs), preferably near where anobstruction is believed to be located; b) detecting radiation emitted bythe radionuclides that are bound to the proteins of the fibrin; and c)forming an image from the detected radiation.
 9. The device of claim 1wherein the step of identifying venous outflow obstruction sitesincludes the steps of: a) applying radionuclides that bind to proteinsspecific to fibrin, such as radionuclides bound to plasmin, otherplasmids or any like substance that dissolves fibrin is bound toinsulin-like growth factor (IGF) binding proteins (IGFBPs), preferablynear where an obstruction is believed to be located; b) detectingradiation emitted by the radionuclides that are bound to the proteins ofthe fibrin; and c) forming an image from the detected radiation.
 10. Thedevice of claim 9 wherein the plasmin, plasmid or other substance thatdissolves fibrin is self-activated.
 11. The device of claim 9 whereinthe plasmin, plasmid or other substance that dissolves fibrin isactivated by the exposure to either a specific light frequency or byultrasound at a specific frequency or any like energy source deliveredeither intravascularly or noninvasively.
 12. The device of claim 11wherein the light or ultrasound or both is via the distal optics ortransducer, respectively.
 13. The device of claim 1 wherein the step ofassessing the nature of the stenotic lesion includes applying an imagingsystem to suspected areas of narrowing or flow disruption to identifyintraluminal abnormalities including webs, flaps, inverted orincompetent valves and membranes as well as stenoses caused by plaque orthe buildup of fibrin or thrombus.
 14. The device of claim 13 whereinthe imaging system is selected from the group consisting of an IVUSsystem, an OCT system, and a combination IVUS and OCT system.
 15. Thedevice of claim 14 wherein the step of determining the pressure gradientacross the stenosis as compared to the superior vena cava is performedusing either a manometer, pressure wire or any other blood pressuremeasuring device if the suspected significant venousstenosis/intraluminal abnormality is confirmed by any of the methods ofstep b.
 16. The device of claim 15 further including the step ofcommunicating information on the pressure gradient to a healthcareprovider.
 17. A Pulmonary Embolism diagnostic device comprising: apressure sensing device sized and shaped for insertion into a patient'sveins; a computing device in communication with the pressure sensingdevice, the computing device configured to perform the steps of:identifying venous outflow obstruction sites in pulmonary vessels;assessing the nature of a stenotic lesion associated with at least oneof the identified venous outflow obstruction sites in the pulmonaryvessels; and determining the pressure gradient across the stenoticlesion as compared to the superior vena cava based on pressuremeasurements obtained by the pressure sensing device.
 18. The device ofclaim 17, wherein the pressure sensing device is a guidewire.
 19. Thedevice of claim 18, wherein the step of identifying venous outflowobstruction sites in pulmonary vessels includes sequentially accessingpulmonary vessels by selective venography at each of these sites toconfirm or exclude a significant stenosis or flow disruption.
 20. Thedevice of claim 18, wherein the step of identifying venous outflowobstruction sites in pulmonary vessels includes using transcutaneousechography applied to an accessible section of a pulmonary vein toidentify venous outflow obstruction sites and to confirm or exclude asignificant stenosis or flow disruption at those sites.